Prewriting strategies

I haven't actually used forms of prewriting too often in my past writings. They are incredibly helpful, don't get me wrong, but all too often I get bogged down by the process of trying to lay all my ideas out on the table, and so many times I simply start with an introduction, and start snowballing from there. Some effective strategies, however, are writing consecutive drafts before you finalize the structure of your ideas, and even brainstorming your ideas into bubble-charts and venn diagrams. These allow you to physically see your ideas in front of you, and even list them in your mind in order of importance.